1. Field of the Invention
The present invention relates, in general, to electrical connectors and, more specifically, to radially resilient electrical sockets, also referred to as barrel terminals, in which a solid, cylindrical electrical prong or pin is axially inserted into a socket whose interior surface is defined by a plurality of contact strips or wires mounted within a cylindrical sleeve and inclined between angularly offset ends.
2. Description of the Art
Radially resilient electrical sockets or barrel terminals are a well known type of electrical connector as shown in U.S. Pat. Nos. 4,657,335 and 4,734,063, both assigned to the assignee of the present invention.
In such electrical sockets or barrel terminals, a generally rectangular stamping is formed with two transversely extending webs spaced inwardly from and parallel to opposite end edges of the sheet. Between the inner side edges of the transverse web, a plurality of uniformly spaced, parallel slots are formed to define a plurality of uniformly spaced, parallel, longitudinally extending strips which are joined at opposite ends to the inward side edges of both transverse webs. Other longitudinally extending slots are coaxially formed in the sheet and extend inwardly from the end edges of the blank to the outer side edges of the transverse webs to form a plurality of uniformly spaced, longitudinally extending tabs projecting outwardly from each transverse web.
The blank or sheet is then formed into a cylinder with the longitudinal strips extending parallel to the axis of the now cylindrical sheet. A closely fitting cylindrical sleeve is slipped coaxially around the outer periphery of the cylindrical blank, and extends axially substantially between the outer edges of the transverse webs. The mounting tabs at each end of the blank are then bent outwardly across end edges of the sleeve into radially extending relationship to the sleeve.
A relatively tight-fitting annular collar or outer barrel is then axially advanced against the radially projecting tabs at one end of the sleeve and slipped over the one end of the sleeve driving the tabs at that end of the sleeve downwardly into face-to-face engagement with the outer surface of the one end of the sleeve. The fit of the annular collar to the sleeve is chosen so that the end of the cylindrical blank at which the collar is located is fixedly clamped to the sleeve against both axial or rotary movement relative to the sleeve. A tool typically having an annular array of uniformly spaced, axially projecting teeth is then engaged with the radially projecting tabs at the opposite end of the sleeve. The teeth on the tool are located to project axially between the radially projecting tabs closely adjacent to the outer surface of the cylindrical sleeve. The tool is then rotated about the longitudinal axis of the cylindrical sleeve while the sleeve is held stationary to rotatably displace the engaged tabs approximately 15xc2x0 to 45xc2x0 from their original rotative orientation relative to the sleeve and the bent over tabs at the opposite end of the sleeve. A second annular collar or outer barrel is then fitted over the tabs and the sleeve to fixedly locate the opposite end of the blank in a rotatably offset position established by the tool before the tool is withdrawn. When completed, such an electrical socket has longitudinal strips extending generally along a straight line between the angularly offset locations adjacent the opposite ends of the cylindrical sleeve. The internal envelope cooperatively defined by the longitudinal strips is a surface of revolution coaxial to the axis of the cylindrical sleeve having equal maximum radii at the points where the strips are joined to the respective webs and a somewhat smaller radius midway of the length of the strips. The minimum radius, midway between the opposite ends of the strips, is selected to be slightly less than the radius of a cylindrical connector pin which is to be inserted into the barrel socket so that the insertion of the pin requires the individual longitudinal strips to stretch slightly longitudinally to firmly frictionally grip the pin when it is seated within the barrel socket.
To put it another way, because of the angular offset orientation of the opposed ends of each of the strips, each strip is spaced from the inner wall of the sleeve in a radial direction progressively reaching a maximum radial spacing with respect to the outer sleeve midway between the ends of the sleeve.
Such a radially resilient electrical barrel socket provides an effective electrical connector which provides secure engagement with an insertable pin; while still enabling easy manual withdrawal or insertion of the pin relative to the socket. Such connectors also provide a large electrical contact area between the pin and the socket which enables such connectors to be employed in high current applications.
Due to the advantages afforded by such a radially resilient electrical connector, it would be desirable to provide new applications for the radially resilient electrical socket or connector.
The present invention is a radially resistent connector formed as a cartridge having a sleeve surrounding a contact member formed of a plurality of spaced strips, with one end of the strips angularly offset from the other end of the strips.
According to one aspect of the invention, an electrical connector includes a cylindrical sleeve, and a contact member coaxially received within the sleeve. The contact member includes a plurality of circumferentially spaced strips having first and second ends, with one of the first and second ends of each strip being angularly offset with respect to a longitudinal axis of the sleeve from the opposed ends of the respective strip. The first and second ends of the strips are non-moveably fixed in the angularly offset position with respect to the sleeve.
In another aspect, the cartridge is mountable in an electrical terminal. The mounting means comprises welds, tabs which are crimped around the edge of the terminal, tabs on the terminal which are bendable over the ends of the mounting flange, tabs in the mounting flange which are formed into enlarged heads extending through apertures in the terminal.
In another aspect, the connector is useable in an electrical disconnect in which two electrical contact members insulatingly spaced apart on a insulating member.
A housing surrounds the spaced contacts and defines a cavity between the housing and the spaced contacts. The connector is releasably insertable into the housing and electrically connects the two contacts. In this aspect, the first contact is connected to a first external electrical circuit and the second electrical contact is connected to a second external electrical circuit. Further, an insulating member connected to the connector to facilitate insertion and removal of the connector with respect to the housing.
A cartridge insertion tool is also provided for the connector. The too includes a cylindrical sleeve, and a contact member coaxially received within the sleeve. The contact member is formed of a plurality of circumferentially spaced strips having first and second ends, one of the first and second ends of each strip being angularly offset with respect to a longitudinal axis of the sleeve from the opposed end of the respective strip. The first and second ends of the strips are non-moveably fixed in the angularly offset position with respect to the sleeve.
The insertion tool also includes a housing having a through bore, a slider notably mounted in the through bore, and a transverse opening in the housing communicating with the bore for insertion of the connector therein.
Advance of the slider in the bore urges the connector into a bore in a use element located at the end of the housing.
The radially resilient electrical connector of the present invention is useable in a number of different applications without modification to the connector. The use of the insertion tool allows the connector to be installed in a use element in the field, rather than at the manufacturing facility of the use element. This facilitates repair and replacement of the connector as well as its use in various use elements.